Ecc report 173 Fixed Service in Europe
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P-MP and MP-MP networksOverviewP-MP networks are usually deployed in a dense manner employing the star configuration for their networking topology. It is necessary to ensure the transmission of high data rates between the base and terminal stations, and, at the same time, minimise the possible intra-system interference between different cells/sectors of the network. Due to the fact that link budgets for P-MP networks, by nature of their design, will be different for differing terminal stations, the appropriate modulation scheme to be employed in a scenario of different terminal stations should be carefully studied. An example of adaptive modulation in P-MP context is given in Figure . 
Figure : Example of using adaptive modulation in a P-MP network, serving terminals with different link budgets Multipoint-to-multipoint networks (MP-MP), also known as meshed networks, are intended to serve a large number of densely located fixed terminal stations. Meshed networks would therefore provide an alternative for P-MP networks. Meshed networks do not require central (base) stations for communications between terminal stations. Instead, each and every terminal station may act as a repeater and pass on the traffic to/from the next terminal station. Such networks would have only one or few drop nodes, which would provide interconnection of the meshed access network to the core transport network. Usually, all the nodes of the meshed network are located on the customer’s premises and act as both customer access and network repeater. In such a way traffic is routed to the addressed customer via one or many repeaters. Nodes located at the edge of the network initially act as terminating points, however may be later converted into repeaters with the further growth of the network, see Figure . 
Figure : Topology example in a mesh network Previously, minimal investment has been made in the P-MP and Multipoint-to-Multipoint (MP-MP) networks, owing to the lack of interest and difficult network planning prior to the adoption of block allocation in dedicated bands, the only evolution that was seen was related to the convergence with mobile applications in lower frequency bands. However P-MP has recently gained interest with the new generation of P-MP equipment available on the market. P-MP may be a useful element in the architecture, including mobile backhauling, for carrying packet data traffic in networks. P-MP networks are finding application for providing last mile connections for mobile broadband networks. P-MP is suited to carrying the data traffic that is becoming the predominant type of information carried over mobile networks. When cellular mobile networks first appeared in the 80’s, they carried voice traffic. Later text messaging and then mobile data were introduced. Mobile data is quickly overtaking voice as the dominant form of traffic on mobile networks. P-MP equipment is based on the observation that mobile data has one characteristic that makes it particularly challenging for FS link networks. Because packet data volume is based on the nature of the data usage characteristics of the users on the network, the traffic presented to the link has a distinct ‘shape’ – transient, unsynchronised peaks when users or applications are consuming data and troughs when users are idle. Such peaks and troughs are no longer correlated with a specific ‘busy hour’ that is common across the whole network (although an overall diurnal ‘swell’ may still be observed). The unpredictable nature of this data traffic makes it difficult for operators to design their network backhaul connections. P-MP networks can address this challenge by statistically multiplexing the traffic from multiple sites to improve the efficiency of the network (see Figure ). That allows the traffic to be merged so that the peaks from one mast ‘cancel out’ the troughs of another which improves system efficiency. 
Figure : Example of statistical multiplexing gain FWA Networks technology trendUntil around year 2000, when the forecast for development of FWA networks were much more encouraging, in particular in millimetric frequency bands, the "technology fight" between P-MP and MP-MP technologies, both claimed to be the best choice, was very strong. However, while first generation of P-MP networks were already in place and tested and commercially available, the proponents of MP-MP structures had soon disappeared due to the investment cuts in the field of “pure” FWA, in particular for the millimetric bands where most of the MP-MP studies aimed to; the market had, de facto, no opportunity of real testing MP-MP systems and networks. Therefore, no new development is expected in the MP-MP field. On the contrary, P-MP systems have been deployed and new generation of equipment are on the market. New products in higher frequencies have been developed and released in most of the popular P-MP bands including 10 GHz, 26, 28 GHz and 42 GHz. In addition, in the lower frequency band, P-MP gained more momentum from the advent of BWA requirements on the market, where FWA and MWA are converging. Next section describes in detail the current situation in the field of BWA. BWA NetworksWith increased regulatory liberalisation and particularly in some lower frequency bands (currently 3400-3600 MHz and 3600-3800 MHz), FWA designations have been replaced with BWA designations and in many CEPT countries the original FWA spectrum authorisations have themselves been liberalised to reflect this new flexibility without any change of authorisation ownership. This new BWA designation introduces regulatory flexibility to support fixed, nomadic and mobile services and in many cases the access technology is derived both from fixed and/or mobile standardisation origins for building up Mobile/Fixed Communication Networks (MFCN). Definitions of BWA, FWA, NWA and MWA can be found in Recommendation ITU-R F.1399. Standardisation activities for broadband FWA included the development of the IEEE 802.16 WirelessMAN-SCPHY specification covering the 10-66 GHz frequency range. This was mirrored within ETSI with the development of the HiperACCESS Technical Specification. The IEEE 802.16 standard was first amended to include the Fixed WirelessMAN OFDM PHY specification covering the licensed spectrum bands below 11 GHz. This was mirrored within ETSI with the development of the HiperMAN Technical Specification. Subsequent amendments to the IEEE 802.16 standard have introduced the WirelessMAN OFDMA PHY for licensed spectrum bands below 11GHz with increasing support for mobile operation within the liberalised BWA spectrum designations. Further enhancements of the WirelessMAN OFDMA PHY have resulted in its adoption into the IMT technology family. The WiMAX Forum industry body supported a standardised implementation of the IEEE 802.16 specification and has developed an accredited equipment certification process to ensure multi-vendor interoperability. WiMAX Certified products are available based on the WirelessMAN OFDM PHY specification targeting the 3400-3600 MHz band.
In lower frequency bands mobile applications are dominant so spectrum availability is limited for BWA/FWA. The 3400-3600MHz and 3600-3800 MHz ranges are the most popular for BWA and underpinned by harmonisation measures in ECC/DEC(07)02 and EC Decision 2008/411/EC. However, following the identification of the frequency range 3400-3600 MHz for IMT systems at WRC-07, the mobile usage in this frequency range is likely to grow in coming years: the ECC has produced a new ECC Decision (ECC/DEC/(11)06) harmonising the band arrangements for MFCN usage (including IMT) in these bands. This complements the BWA framework with specific harmonised frequency channel arrangements. It should be noted that ECC/DEC/(11)06 provides, in 3400-3600 MHz, arrangements for both FDD and TDD systems, while, in 3600-3800 MHz, only TDD arrangements are considered; this should be taken into account also when simple FWA networks (including, when appropriate, backhauling infrastructure) are considered. In the lightly licensed 5.8 GHz frequency band FWA (fixed and nomadic) operation continues to be possible on a national basis under the framework set by ECC Recommendation ECC/REC(06)04 and ETSI Harmonised Standard EN302 502. Coexistence considerations result in a low EIRP constraints and a need to implement a demanding Dynamic Frequency Selection (DFS) feature for the protection of primary Radiodetermination service. Frequency bands above 10 GHz In these frequency bands, 10.5, 26, 28 and 32 GHz despite early FWA standardisation efforts in ETSI and IEEE, technology costs remained high and commercial uncertainty prevented widespread take up and deployment for access applications. In addition, the 42GHz frequency band, originally designated for exclusive Multimedia Wireless Systems (MWS) use (ECC/DEC(99)15) in 2009, was not exploited anywhere in Europe, apart from some applications in the Russian Federation. Thus during 2010 the ECC decided to open this frequency band also to P-P links in order to relieve link congestion in 38 GHz band which is heavily used for mobile backhauling. However the recent explosion in data demand over mobile networks and the very rapid evolution of mobile technologies could lead to future renewed interest in the capacity of the higher frequency bands particularly in the light of technological developments that could lead to effective commercialization of new infrastructures in multipoint technology in these frequencies. Directory: Docs -> doc98 -> official -> Word Docs -> Borzoi Club of America Register of Merit Program I. What is a Register Of Merit Docs -> Protecting the rights of the child in the context of migration Docs -> United Nations E/C. 12/Esp/5 Docs -> 9th May 1950 the schuman declaration Docs -> Getting To Outcomes® in Services for Homeless Veterans 10 Steps for Achieving Accountability Word -> Service provider access in mobile networks Word -> Explanatory memorandum introduction Word -> Ecc report 194 Extra-Territorial Use of E. 164 Numbers approved April 2013 Executive summary Download 0.53 Mb. Share with your friends:
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